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Dive into the research topics where Nanne Kleefstra is active.

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Featured researches published by Nanne Kleefstra.


Diabetes Care | 2010

Metformin associated with lower cancer mortality in type 2 diabetes: ZODIAC-16.

Gijs W. D. Landman; Nanne Kleefstra; Kornelis J. J. van Hateren; Klaas H. Groenier; Rijk O. B. Gans; Henk J. G. Bilo

OBJECTIVE Several studies have suggested an association between specific diabetes treatment and cancer mortality. We studied the association between metformin use and cancer mortality in a prospectively followed cohort. RESEARCH DESIGN AND METHODS In 1998 and 1999, 1,353 patients with type 2 diabetes were enrolled in the Zwolle Outpatient Diabetes project Integrating Available Care (ZODIAC) study in the Netherlands. Vital status was assessed in January 2009. Cancer mortality rate was evaluated using standardized mortality ratios (SMRs), and the association between metformin use and cancer mortality was evaluated with a Cox proportional hazards model, taking possible confounders into account. RESULTS Median follow-up time was 9.6 years, average age at baseline was 68 years, and average A1C was 7.5%. Of the patients, 570 died, of which 122 died of malignancies. The SMR for cancer mortality was 1.47 (95% CI 1.22–1.76). In patients taking metformin compared with patients not taking metformin at baseline, the adjusted hazard ratio (HR) for cancer mortality was 0.43 (95% CI 0.23–0.80), and the HR with every increase of 1 g of metformin was 0.58 (95% CI 0.36–0.93). CONCLUSIONS In general, patients with type 2 diabetes are at increased risk for cancer mortality. In our group, metformin use was associated with lower cancer mortality compared with nonuse of metformin. Although the design cannot provide a conclusion about causality, our results suggest a protective effect of metformin on cancer mortality.


Diabetes Care | 2008

Skin Autofluorescence: A Tool to Identify Type 2 Diabetic Patients at Risk for Developing Microvascular Complications

Esther G. Gerrits; Helen L. Lutgers; Nanne Kleefstra; Reindert Graaff; Klaas H. Groenier; Andries J. Smit; Rijk O. B. Gans; Henk J. G. Bilo

OBJECTIVE—Skin autofluorescence is a noninvasive measure of the level of tissue accumulation of advanced glycation end products, representing cumulative glycemic and oxidative stress. Recent studies have already shown a relationship between skin autofluorescence and diabetes complications, as well as the predictive value of skin autofluorescence for total and cardiovascular mortality in type 2 diabetes. Our aim was to investigate the predictive value of skin autofluorescence for the development of microvascular complications in type 2 diabetes. RESEARCH DESIGN AND METHODS—At baseline, skin autofluorescence of 973 type 2 diabetic patients with well-controlled diabetes was noninvasively measured with an autofluorescence reader. The aggregate clinical outcome was defined as the development of any diabetes-associated microvascular complication of 881 surviving patients, which was assessed at baseline and at the end of follow-up. Single end points were the development of diabetes-associated retinopathy, neuropathy, and (micro)albuminuria. RESULTS—After a mean follow-up period of 3.1 years, baseline skin autofluorescence was significantly higher in patients who developed any microvascular complication, neuropathy, or (micro)albuminuria but not in those who developed retinopathy. Multivariate analyses showed skin autofluorescence as a predictor for development of any microvascular complication along with A1C, for development of neuropathy along with smoking, and for development of (micro)albuminuria together with sex, A1C, and diabetes duration. Skin autofluorescence did not have predictive value for the development of retinopathy, albeit diabetes duration did. CONCLUSIONS—Our study is the first observation of skin autofluorescence measurement as an independent predictor of development of microvascular complications in type 2 diabetes.


Journal of The American Society of Nephrology | 2015

Diagnosis and Prediction of CKD Progression by Assessment of Urinary Peptides

Joost P. Schanstra; Petra Zürbig; Alaa Alkhalaf; Àngel Argilés; Stephan J. L. Bakker; Joachim Beige; Henk J. G. Bilo; Christos Chatzikyrkou; Mohammed Dakna; Jesse Dawson; Christian Delles; Hermann Haller; Marion Haubitz; Holger Husi; Joachim Jankowski; George Jerums; Nanne Kleefstra; Tatiana Kuznetsova; David M. Maahs; Jan Menne; William Mullen; Alberto Ortiz; Frederik Persson; Peter Rossing; Piero Ruggenenti; Ivan Rychlik; Andreas L. Serra; Justyna Siwy; Janet K. Snell-Bergeon; Goce Spasovski

Progressive CKD is generally detected at a late stage by a sustained decline in eGFR and/or the presence of significant albuminuria. With the aim of early and improved risk stratification of patients with CKD, we studied urinary peptides in a large cross-sectional multicenter cohort of 1990 individuals, including 522 with follow-up data, using proteome analysis. We validated that a previously established multipeptide urinary biomarker classifier performed significantly better in detecting and predicting progression of CKD than the current clinical standard, urinary albumin. The classifier was also more sensitive for identifying patients with rapidly progressing CKD. Compared with the combination of baseline eGFR and albuminuria (area under the curve [AUC]=0.758), the addition of the multipeptide biomarker classifier significantly improved CKD risk prediction (AUC=0.831) as assessed by the net reclassification index (0.303±-0.065; P<0.001) and integrated discrimination improvement (0.058±0.014; P<0.001). Correlation of individual urinary peptides with CKD stage and progression showed that the peptides that associated with CKD, irrespective of CKD stage or CKD progression, were either fragments of the major circulating proteins, suggesting failure of the glomerular filtration barrier sieving properties, or different collagen fragments, suggesting accumulation of intrarenal extracellular matrix. Furthermore, protein fragments associated with progression of CKD originated mostly from proteins related to inflammation and tissue repair. Results of this study suggest that urinary proteome analysis might significantly improve the current state of the art of CKD detection and outcome prediction and that identification of the urinary peptides allows insight into various ongoing pathophysiologic processes in CKD.


Diabetes Care | 2007

Chromium Treatment Has No Effect in Patients With Type 2 Diabetes in a Western Population A randomized, double-blind, placebo-controlled trial

Nanne Kleefstra; Sebastiaan T. Houweling; Stephan J. L. Bakker; Simon Verhoeven; Rijk O. B. Gans; Betty Meyboom-de Jong; Henk J. G. Bilo

OBJECTIVE—Chromium treatment has been reported to improve glycemic control in patients with type 2 diabetes. However, concern exists about the possible toxic effects of chromium picolinate. The aim of this study was to determine the effect of chromium treatment in the form of chromium yeast on glycemic control in a Western population of patients with type 2 diabetes who were being treated with oral hypoglycemic agents. RESEARCH DESIGN AND METHODS—In this 6-month, double-blind study, patients with moderate glycemic control, being treated with oral hypoglycemic agents, were randomly assigned to receive either a placebo or treatment with 400 μg of chromium daily in the form of chromium yeast. The primary efficacy parameter was a change in A1C. Secondary end points were changes in lipid profile, BMI, blood pressure, body fat, and insulin resistance. RESULTS—No differences were found for the change in A1C between the intervention and placebo groups, nor were any differences found between the groups for the secondary end points. CONCLUSIONS—There is no evidence that chromium in the form of chromium yeast is effective in improving glycemic control in Western patients with type 2 diabetes who are taking oral hypoglycemic agents.


Diabetes Care | 2010

A Double-Blind, Randomized, Placebo-Controlled Clinical Trial on Benfotiamine Treatment in Patients With Diabetic Nephropathy

Alaa Alkhalaf; Astrid Klooster; Willem van Oeveren; Ulrike Achenbach; Nanne Kleefstra; Robbert J. Slingerland; G. Sophie Mijnhout; Henk J. G. Bilo; Reinold Gans; Gerjan Navis; Stephan J. L. Bakker

OBJECTIVE To investigate the effect of benfotiamine on urinary albumin excretion (UAE) and the tubular damage marker kidney injury molecule-1 (KIM-1) in patients with type 2 diabetes and nephropathy. RESEARCH DESIGN AND METHODS Patients with type 2 diabetes and UAE equivalent to 15–300 mg/24 h, despite ACE inhibitors (ACE-Is) or angiotensin receptor blockers (ARBs), were randomly assigned to 12 weeks of benfotiamine (900 mg/day) (n = 39) or placebo (n = 43). RESULTS Compared with placebo, benfotiamine treatment resulted in significant improvement of thiamine status (P < 0.001). Benfotiamine treatment did not significantly decrease 24-h UAE or 24-h KIM-1 excretion. CONCLUSIONS In patients with type 2 diabetes and nephropathy, high-dose benfotiamine treatment for 12 weeks in addition to ACE-Is or ARBs did not reduce UAE or KIM-1 excretion, despite improvement of thiamine status.


Diabetes Care | 2010

Health-Related Quality of Life and Mortality in a General and Elderly Population of Patients With Type 2 Diabetes (ZODIAC-18)

Gijs W. D. Landman; Kornelis J. J. van Hateren; Nanne Kleefstra; Klaas H. Groenier; Rijk O. B. Gans; Henk J. G. Bilo

OBJECTIVE Diabetes negatively impacts the health-related quality of life (HRQOL) of patients with type 2 diabetes. An earlier analysis showed HRQOL to be associated with mortality, which suggests that measuring HRQOL could have clinical implications. We studied the association between HRQOL and total and cardiovascular mortality in patients with type 2 diabetes during long-term follow-up and specifically focused on old age and sex differences. RESEARCH DESIGN AND METHODS HRQOL was measured in a prospectively followed cohort of 1,353 patients with type 2 diabetes using the RAND-36. Cox proportional hazard models were used to measure the independent effect of baseline HRQOL on mortality. RESULTS During a mean follow-up of 9.6 years, 570 (42%) patients died, 280 of whom died of cardiovascular disease (49%). The Physical Component Score (PCS) and the Mental Component Score (MCS) were inversely associated with total mortality, with hazard ratios of 0.988 (95% CI 0.983–0.993) and 0.990 (95% CI 0.985–0.995), respectively. A 10-point-higher score on the PCS and MCS decreased the risk for total mortality by 11 and 10%, respectively. An inverse relationship with mortality was also seen for men, women, and for patients aged >75 years. Mental health was significantly related to mortality in men but not in women. CONCLUSIONS Lower physical and mental HRQOL was associated with a higher total mortality and cardiovascular mortality in patients with type 2 diabetes; this is also the case when studying men and women and the elderly separately. The dimension mental health, related to depression and anxiety, was only associated with mortality in men, not in women.


Age and Ageing | 2010

Lower blood pressure associated with higher mortality in elderly diabetic patients (ZODIAC-12)

Kornelis J. J. van Hateren; Gijs W. D. Landman; Nanne Kleefstra; Klaas H. Groenier; Adriaan M. Kamper; Sebastiaan T. Houweling; Henk J. G. Bilo

OBJECTIVE to investigate the relationship between blood pressure over time and mortality in elderly patients with type 2 diabetes mellitus (T2DM). DESIGN prospective observational cohort study. SETTING primary care, Zwolle, The Netherlands. SUBJECTS patients with T2DM aged 60 years and older (n = 881). The cohort was divided into two age categories: 60-75 years and older than 75 years. METHODS updated means for systolic, diastolic and pulse pressures were calculated after a median follow-up time of 9.8 years. These values were used as time-dependent covariates in a Cox proportional hazard model. Main outcome measures were all-cause and cardiovascular mortality. RESULTS all of the blood pressure measures were inversely related to all-cause mortality in elderly diabetic patients (>75 years). Furthermore, these relationships were specifically found in elderly patients treated with antihypertensive medication at baseline. A decrease of 10 mm Hg in systolic blood pressure, diastolic blood pressure and pulse pressure led to a mortality increase of 22% [95% confidence interval (95% CI): 13-31%], 30% [95% CI: 13%-46%] and 22% [95% CI: 11%-33%], respectively. In the low age group (60-75 years), no relationship was found between blood pressure and mortality. CONCLUSIONS blood pressure is a marker for mortality in elderly T2DM patients; however, the relationship is inverse.


Journal of Clinical Nursing | 2011

Can diabetes management be safely transferred to practice nurses in a primary care setting? A randomised controlled trial

Sebastiaan T. Houweling; Nanne Kleefstra; Kornelis J. J. van Hateren; Klaas H. Groenier; Betty Meyboom-de Jong; Henk J. G. Bilo

AIMS AND OBJECTIVES To determine whether the management of type 2 diabetes mellitus in a primary care setting can be safely transferred to practice nurses. BACKGROUND Because of the increasing prevalence of type 2 diabetes mellitus and the burden of caring for individual patients, the demand type 2 diabetes mellitus patients place on primary health care resources has become overwhelming. DESIGN Randomised controlled trial. METHODS The patients in the intervention group were cared for by practice nurses who treated glucose levels, blood pressure and lipid profile according to a specified protocol. The control group received conventional care from a general practitioner. The primary outcome measure was the mean decrease seen in glycated haemoglobin (HbA1c) levels at the end of the follow-up period (14 months). RESULTS A total of 230 patients was randomised with 206 completing the study. The between-group differences with respect to reduction in HbA1c, blood pressure and lipid profile were not significant. Blood pressure decreased significantly in both groups; 7.4/3.2 mm Hg in the intervention group and 5.6/1.0 mm Hg in the control group. In both groups, more patients met the target values goals for lipid profile compared to baseline. In the intervention group, there was some deterioration in the health-related quality of life and an increase in diabetes-related symptoms. Patients being treated by a practice nurse were more satisfied with their treatment than those being treated by a general practitioner. CONCLUSION Practice nurses achieved results, which were comparable to those achieved by a general practitioner with respect to clinical parameters with better patient satisfaction. RELEVANCE TO CLINICAL PRACTICE This study shows that diabetes management in primary care can be safely transferred to practice nurses.


Journal of Hypertension | 2007

Effect of device-guided breathing exercises on blood pressure in hypertensive patients with type 2 diabetes mellitus : A randomized controlled trial

S. J. J. Logtenberg; Nanne Kleefstra; Sebastiaan T. Houweling; Klaas H. Groenier; Henk J. G. Bilo

Objective In patients with type 2 diabetes mellitus (DM2), it is hard to reach treatment objectives for blood pressure (BP) with classical treatment options. Recently, reducing breathing frequency has been advocated as a method to reduce BP. We examined if an electronic device such as Resperate, by reducing breathing frequency, would lead to BP reduction in a population of patients with DM2 and hypertension. Our secondary objective was to study the effect of this device on quality of life (QOL). Methods A randomized, single-blind, controlled trial was conducted over a period of 8 weeks to evaluate the effect of this therapy on BP and QOL. The control group listened to music and used no other therapeutic device. BP and QOL changes were studied in 30 patients with DM2 and hypertension. Results There was no significant difference in change in BP between groups; −7.5 [95% confidence interval (CI) −12.7, −2.3]/−1.0 (95% CI −5.5, 3.6) mmHg in the intervention group and −12.2 (95% CI −17.4, −7.0)/−5.5 (95% CI −9.7, −1.4) mmHg in the control group. Whether or not the target breathing frequency of 10 breaths/min was reached did not affect BP. There were no significant changes in QOL. Conclusions The effects of Resperate on BP and QOL were not significantly different from those found in the control group. Furthermore, 40% of patients did not reach the target breathing frequency, making this device less suitable for clinical practice in patients with DM2.


Diabetes Care | 2009

Improved Glycemic Control With Intraperitoneal Versus Subcutaneous Insulin in Type 1 Diabetes: A randomized controlled trial

S. J. J. Logtenberg; Nanne Kleefstra; Sebastiaan T. Houweling; Klaas H. Groenier; Reinold Gans; Evert van Ballegooie; Henk J. G. Bilo

OBJECTIVE Continuous intraperitoneal insulin infusion (CIPII) with an implantable pump has been available for the past 25 years. CIPII, with its specific pharmacodynamic properties, may be a viable treatment alternative to improve glycemic control in patients with type 1 diabetes for whom other therapies have failed. There have been few studies in which CIPII was compared with subcutaneous insulin treatment for patients with type 1 diabetes with poor glycemic control. RESEARCH DESIGN AND METHODS In an open-label, prospective, crossover, randomized, 16-month study, the effects of CIPII and subcutaneous insulin were compared in 24 patients. The primary outcome measure was the incidence of hypoglycemia. Secondary outcome measures were A1C, and glucose profile, including time in euglycemia, as measured by continuous glucose monitoring. RESULTS The incidence of grade 1 hypoglycemic events was 4.0 ± 2.6 per week with subcutaneous insulin compared with 3.5 ± 2.3 per week during CIPII (P = 0.13). The absolute mean difference in A1C with CIPII compared with subcutaneous treatment was −0.76% (95% CI −1.41 to −0.11) (P = 0.03). Baseline time spent in euglycemia was 45.2 ± 12.6% and increased 10.9% (4.6–17.3) with CIPII compared with subcutaneous treatment (absolute value; P = 0.003). There were no differences in the occurrence rate for severe hypoglycemic events, daily insulin use, or BMI. No pump or catheter malfunction was observed during the study. CONCLUSIONS Although we did not observe a significant reduction in hypoglycemic events, improved glycemic control was achieved with the use of CIPII. We saw a 0.8% decrease in A1C and an 11% increase in the time spent in euglycemia.

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Henk J. G. Bilo

University Medical Center Groningen

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Klaas H. Groenier

University Medical Center Groningen

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Gijs W. D. Landman

University Medical Center Groningen

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Sebastiaan T. Houweling

University Medical Center Groningen

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S. J. J. Logtenberg

University Medical Center Groningen

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Stephan J. L. Bakker

University Medical Center Groningen

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Peter R. van Dijk

University Medical Center Groningen

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Rijk O. B. Gans

University Medical Center Groningen

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Alaa Alkhalaf

University Medical Center Groningen

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